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911.
The effect of one massive dose of cytoxan (150 mg/kg), as an alkylating agent, on the morphology of sarcoma 180 cells was followed after 1, 3, 6, 12, 24, 48, 96, 120, and 168 h. After 1 h the cells of treated tumour showed clumping and a decrease in their size. In addition, statistical analysis manifested significant decrease in all phases of mitotic figures. All mitotic figures were completely stopped after 3 h from cytoxan treatment. After 6 and 12 h from cytoxan treatment the hyaline degenerations became more marked in the treated tumour tissue. Chromosomal bridge formation, nuclei aberrations and polynuclear cells were more prominent in 24, 48, and 96 h from cytoxan treatment. Increase in the nuclear size and hyaline degeneration were observed in treated section of 120 and 168 h.  相似文献   
912.
The differentiation of spermatids in the marmoset (Callithrix jacchus, n = 9) testis is described here at the light-microscopic level employing serial semithin sections. The definition of 8 different phases of spermiogenesis, i.e. the formation of spermatids, is based upon the changes in the development of nucleus, acrosome and flagellum.  相似文献   
913.
A rapid, direct method for screening single cell-derived colonies or foci is described. The method allows the screening of a large number of colonies or foci by nitrocellulose filter hybridization using DNA probes. This technique simplifies current screening procedures and is a reliable, rapid, and sensitive method for the selection of cell clones containing a desired transfected gene.  相似文献   
914.
915.
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917.
Cimetidine is widely prescribed for the treatment of peptic ulcer disease and has recently been shown to inhibit the metabolism of warfarin, antipyrine and diazepam. To further examine this phenomenon we investigated the effect of various doses of cimetidine and other related drugs on 14C-aminopyrine, 14C-phenacetin and 14C-caffeine breath tests. Cimetidine caused a dose-related inhibition of the metabolism of aminopyrine and caffeine but had no effect on the phenacetin breath test. Metiamide, H1-antihistamines, phenothiazines and local anesthetics also inhibited the aminopyrine breath test. Cyproheptadine had no effect on either phenacetin or caffeine elimination. This study demonstrates a complex drug-drug interaction which may have widespread clinical implications.  相似文献   
918.
919.
ELISA is used for detecting the soluble staphylococcal antigen in patients with purulent septic infections. The optimum conditions for the assay have been established: the dose of staphylococcal gamma globulin for plate sensitization should be 5.0-10.0 micrograms/ml, the pH of the buffer solution 9.6-10.0, the time and temperature of incubation 18-20 hours at 4 degrees C or 5 hours at 37 degrees C. The possibility of using plates manufactured in the USSR has been shown. The sensitivity of the above diagnostic test system is 0.005 microgram/ml.  相似文献   
920.
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